Resource Type

1,056 Matching Results

Results open in a new window/tab.

Immigrant Investors: Small Number of Participants Attributed to Pending Regulations and Other Factors (open access)

Immigrant Investors: Small Number of Participants Attributed to Pending Regulations and Other Factors

A letter report issued by the Government Accountability Office with an abstract that begins "In 1990, Congress established an investor visa category, referred to as EB-5, whereby immigrants are granted conditional residence and after 2 years, permanent residence status in the United States if they invest in a commercial enterprise that will benefit the U.S. economy and create at least 10 full-time jobs. The Basic Pilot Program Extension and Expansion Act of 2003 (P.L. 108-156) mandates that GAO provide certain information regarding the EB-5 employment category. In response to the mandate, this report provides information on immigrant participation, including the number of participants, their countries of origin, and the number who sought U.S. citizenship. Also, this report includes information about the types of business established and where they were established."
Date: April 1, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Nuclear Waste Cleanup: DOE Has Made Some Progress in Cleaning Up the Paducah Site, but Challenges Remain (open access)

Nuclear Waste Cleanup: DOE Has Made Some Progress in Cleaning Up the Paducah Site, but Challenges Remain

A letter report issued by the General Accounting Office with an abstract that begins "In 1988, radioactive contamination was found in the drinking water wells of residences near the federal government's uranium enrichment plant in Paducah, Kentucky. In response, the Department of Energy (DOE) began a cleanup program. In 2000, GAO reported that DOE faced significant challenges in cleaning up the site and that it was doubtful that the cleanup would be completed as scheduled by 2010 and within the $1.3 billion cost projection. GAO was asked to determine (1) the amount of money DOE has spent on the site, the purposes for which it was spent, and the estimated total costs for the site; (2) the status of DOE cleanup efforts; and (3) the challenges GAO previously identified that continue to be issues for DOE."
Date: April 1, 2004
Creator: United States. General Accounting Office.
System: The UNT Digital Library
2008 Lobbying Disclosure: Observations on Lobbyists' Compliance with Disclosure Requirements (open access)

2008 Lobbying Disclosure: Observations on Lobbyists' Compliance with Disclosure Requirements

A letter report issued by the Government Accountability Office with an abstract that begins "The Honest Leadership and Open Government Act (HLOGA) of 2007 amended the Lobbying Disclosure Act of 1995 by doubling the frequency of lobbyists' reporting and increasing criminal and civil penalties. This is GAO's second report in response to the Act's requirement for GAO to annually (1) determine the extent to which lobbyists can demonstrate compliance with the Act by providing support for information on their registrations and reports, (2) describe challenges identified by lobbyists to complying with the Act, and (3) describe the resources and authorities available to the U.S. Attorney's Office for the District of Columbia's efforts to enforce the Act. For this report, GAO placed increased emphasis on written documentation to support disclosure reports. GAO reviewed a random sample of 100 lobbyist disclosure reports filed during the first three quarters of calendar year 2008. GAO also selected a random sample of 100 reports of federal political contributions, filed for the first time, for mid-calendar-year 2008. This methodology allowed GAO to generalize the sample results to the populations of 40,169 lobbying activity disclosure reports and 6,048 reports with contributions filed. GAO met with lobbyists regarding …
Date: April 1, 2009
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Social Security Statements: Social Security Administration Should Better Evaluate Whether Workers Understand Their Statements (open access)

Social Security Statements: Social Security Administration Should Better Evaluate Whether Workers Understand Their Statements

A letter report issued by the Government Accountability Office with an abstract that begins "The Social Security Statement is the federal government's main document for communicating with more than 140 million workers about their Social Security benefits. By law, the statement must show an individual's annual earnings, payments into Social Security and Medicare, and projected benefits. The Social Security Administration also uses the statement to explain the various types of Social Security benefits and to encourage greater financial planning for retirement. GAO conducted a review to examine (1) how well recipients understand the current statement, (2) how the Social Security Administration is evaluating the statement's understandability, and (3) the promising practices used by private sector companies and other industrial countries. GAO's information was obtained from its national survey and focus groups of statement recipients, a firm that evaluates benefit statements, officials from three other countries (Canada, Sweden, and the United Kingdom), and other experts from the private sector."
Date: April 1, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Title I: Education Needs to Monitor States' Scoring of Assessments (open access)

Title I: Education Needs to Monitor States' Scoring of Assessments

A letter report issued by the General Accounting Office with an abstract that begins "Concerned that Title I of the Elementary and Secondary Education Act (ESEA) had not significantly improving the educational achievements of children at risk, Congress mandated major changes in 1994. States were required to adopt or develop challenging curriculum content and performance standards, assessments aligned with content standards, and accountability systems to measure progress in raising student achievement. In return, states were given greater flexibility in the use of Title I and other federal funds. The No Child Left Behind Act of 2001 augments the assessment and accountability requirements that states must implement and increases the stakes for schools that fail to make adequate progress. The 1994 legislation required states to comply with the requirements by January 2001 but allowed the Department of Education to extend that deadline. Education has granted waivers to 30 states to give them more time to meet all requirements. If states fail to meet the extended timeliness, they are subject to the withholding of some Title I administrative funds. Title I directors indicated that a state's ability to meet the 1994 requirements improved when both state leaders and state agency staff made …
Date: April 1, 2002
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Habitat for Humanity of Metro Denver Zero Energy Demonstration Home (open access)

Habitat for Humanity of Metro Denver Zero Energy Demonstration Home

This brochure describes the 2005 demonstration home designed by NREL and the Habitat for Humanity of Metro Denver. The completed home produced 24% more energy than it consumed over 12 months.
Date: April 1, 2008
Creator: unknown
System: The UNT Digital Library
Record of Technical Change for the Closure Report for Corrective Action Unit 127: Areas 25 and 26 Storage Tanks (open access)

Record of Technical Change for the Closure Report for Corrective Action Unit 127: Areas 25 and 26 Storage Tanks

None
Date: April 1, 2008
Creator: National Security Technologies, LLC
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 545: Dumps, Waste Disposal Sites, and Buried Radioactive Materials Nevada Test Site, Nevada, Revision 0 (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 545: Dumps, Waste Disposal Sites, and Buried Radioactive Materials Nevada Test Site, Nevada, Revision 0

This Corrective Action Decision Document (CADD)/Closure Report (CR) has been prepared for Corrective Action Unit (CAU) 545, Dumps, Waste Disposal Sites, and Buried Radioactive Materials, in Areas 2, 3, 9, and 20 of the Nevada Test Site, Nevada, in accordance with the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management (1996, as amended February 2008). Corrective Action Unit 545 is comprised of the following eight Corrective Action Sites (CASs): • 02-09-01, Mud Disposal Area • 03-08-03, Mud Disposal Site • 03-17-01, Waste Consolidation Site 3B • 03-23-02, Waste Disposal Site • 03-23-05, Europium Disposal Site • 03-99-14, Radioactive Material Disposal Area • 09-23-02, U-9y Drilling Mud Disposal Crater • 20-19-01, Waste Disposal Site While all eight CASs are addressed in this CADD/CR, sufficient information was available for the following three CASs; therefore, a field investigation was not conducted at these sites: • For CAS 03-08-03, though the potential for subsidence of the craters was judged to be extremely unlikely, the data quality objective (DQO) meeting participants agreed that sufficient information existed about disposal and releases at the site …
Date: April 1, 2008
Creator: Wickline, Alfred
System: The UNT Digital Library
Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds (open access)

Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds

The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were …
Date: April 1, 2008
Creator: Schuster, G. J.; Simonen, F. A. & Doctor, S. R.
System: The UNT Digital Library
CSI: Dognapping workshop : an outreach experiment designed to produce students that are hooked on science. (open access)

CSI: Dognapping workshop : an outreach experiment designed to produce students that are hooked on science.

The CSI: Dognapping Workshop is a culmination of the more than 65 Sandian staff and intern volunteers dedication to exciting and encouraging the next generation of scientific leaders. This 2 hour workshop used a 'theatrical play' and 'hands on' activities that was fun, exciting and challenging for 3rd-5th graders while meeting science curriculum standards. In addition, new pedagogical methods were developed in order to introduce nanotechnology to the public. Survey analysis indicated that the workshop had an overall improvement and positive impact on helping the students to understand concepts from materials science and chemistry as well as increased our interaction with the K-5 community. Anecdotal analyses showed that this simple exercise will have far reaching impact with the results necessary to maintain the United States as the scientific leader in the world. This experience led to the initiation of over 100 Official Junior Scientists.
Date: April 1, 2008
Creator: Boyle, Timothy J.; Gorman, Anna K.; Pratt, Harry D., III; Hernandez-Sanchez, Bernadette A.; Lambert, Timothy N.; Ottley, Leigh Anna M. et al.
System: The UNT Digital Library
Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling; Is Single Pass Cooling Possible? (open access)

Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling; Is Single Pass Cooling Possible?

Electron beam cooling is examined as an option to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster. Electron beam parameters are based on experimental data (obtained at BNL) of electron beams extracted from a plasma cathode. Preliminary calculations indicate that single pass cooling is feasible; momentum spread can be reduced by more than an order of magnitude in less than one meter.
Date: April 1, 2008
Creator: Hershcovitch,A.
System: The UNT Digital Library
Plug-In Hybrid Electric Vehicle Value Proposition Study: Phase 1, Task 2: Select Value Propositions/Business Model for Further Study (open access)

Plug-In Hybrid Electric Vehicle Value Proposition Study: Phase 1, Task 2: Select Value Propositions/Business Model for Further Study

The Plug-In Hybrid Electric Vehicle (PHEV) Value Propositions Workshop held in Washington, D.C. in December 2007 served as the Task 1 Milestone for this study. Feedback from all five Workshop breakout sessions has been documented in a Workshop Summary Report, which can be found at www.sentech.org/phev. In this report, the project team compiled and presented a comprehensive list of potential value propositions that would later serve as a 'grab bag' of business model components in Task 2. After convening with the Guidance and Evaluation Committee and other PHEV stakeholders during the Workshop, several improvements to the technical approach were identified and incorporated into the project plan to present a more realistic and accurate case study and evaluation. The assumptions and modifications that will have the greatest impact on the case study selection process in Task 2 are described in more detail in this deliverable. The objective of Task 2 is to identify the combination of value propositions that is believed to be achievable by 2030 and collectively hold promise for a sustainable PHEV market by 2030. This deliverable outlines what the project team (with input from the Committee) has defined as its primary scenario to be tested in depth for …
Date: April 1, 2008
Creator: Sikes, Karen R; Markel, Lawrence C; Hadley, Stanton W & Hinds, Shaun
System: The UNT Digital Library
Regional Consumer Hydrogen Demand and Optimal Hydrogen Refueling Station Siting (open access)

Regional Consumer Hydrogen Demand and Optimal Hydrogen Refueling Station Siting

Using a GIS approach to spatially analyze key attributes affecting hydrogen market transformation, this study proposes hypothetical hydrogen refueling station locations in select subregions to demonstrate a method for determining station locations based on geographic criteria.
Date: April 1, 2008
Creator: Melendez, M. & Milbrandt, A.
System: The UNT Digital Library
Technical Basis for Assessing Uranium Bioremediation Performance (open access)

Technical Basis for Assessing Uranium Bioremediation Performance

In situ bioremediation of uranium holds significant promise for effective stabilization of U(VI) from groundwater at reduced cost compared to conventional pump and treat. This promise is unlikely to be realized unless researchers and practitioners successfully predict and demonstrate the long-term effectiveness of uranium bioremediation protocols. Field research to date has focused on both proof of principle and a mechanistic level of understanding. Current practice typically involves an engineering approach using proprietary amendments that focuses mainly on monitoring U(VI) concentration for a limited time period. Given the complexity of uranium biogeochemistry and uranium secondary minerals, and the lack of documented case studies, a systematic monitoring approach using multiple performance indicators is needed. This document provides an overview of uranium bioremediation, summarizes design considerations, and identifies and prioritizes field performance indicators for the application of uranium bioremediation. The performance indicators provided as part of this document are based on current biogeochemical understanding of uranium and will enable practitioners to monitor the performance of their system and make a strong case to clients, regulators, and the public that the future performance of the system can be assured and changes in performance addressed as needed. The performance indicators established by this document and …
Date: April 1, 2008
Creator: Long, P. E.; Yabusaki, S. B.; Meyer, P. D.; Murray, C. J. & N’Guessan, A. L.
System: The UNT Digital Library
Durability-Based Design Criteria for a Quasi-Isotropic Carbon-Fiber-Reinforced Thermoplastic Automotive Composite (open access)

Durability-Based Design Criteria for a Quasi-Isotropic Carbon-Fiber-Reinforced Thermoplastic Automotive Composite

This report provides recommended durability-based design properties and criteria for a quais-isotropic carbon-fiber thermoplastic composite for possible automotive structural applications. The composite consisted of a PolyPhenylene Sulfide (PPS) thermoplastic matrix (Fortron's PPS - Ticona 0214B1 powder) reinforced with 16 plies of carbon-fiber unidirectional tape, [0?/90?/+45?/-45?]2S. The carbon fiber was Hexcel AS-4C and was present in a fiber volume of 53% (60%, by weight). The overall goal of the project, which is sponsored by the U.S. Department of Energy's Office of Freedom Car and Vehicle Technologies and is closely coordinated with the Advanced Composites Consortium, is to develop durability-driven design data and criteria to assure the long-term integrity of carbon-fiber-based composite systems for automotive structural applications. This document is in two parts. Part 1 provides design data and correlations, while Part 2 provides the underlying experimental data and models. The durability issues addressed include the effects of short-time, cyclic, and sustained loadings; temperature; fluid environments; and low-energy impacts (e.g., tool drops and kickups of roadway debris) on deformation, strength, and stiffness. Guidance for design analysis, time-independent and time-dependent allowable stresses, rules for cyclic loadings, and damage-tolerance design guidance are provided.
Date: April 1, 2006
Creator: Naus, Dan J; Corum, James; Klett, Lynn B; Davenport, Mike; Battiste, Rick & Simpson, Jr., William A
System: The UNT Digital Library
Laboratory Directed Research and Development Program FY 2005 Annual Report (open access)

Laboratory Directed Research and Development Program FY 2005 Annual Report

The Oak Ridge National Laboratory (ORNL) Laboratory Directed Research and Development (LDRD) Program reports its status to the U.S. Department of Energy (DOE) in March of each year. The program operates under the authority of DOE Order 413.2A, 'Laboratory Directed Research and Development' (January 8, 2001), which establishes DOE's requirements for the program while providing the Laboratory Director broad flexibility for program implementation. LDRD funds are obtained through a charge to all Laboratory programs. This report describes all ORNL LDRD research activities supported during FY 2005 and includes final reports for completed projects and shorter progress reports for projects that were active, but not completed, during this period. The FY 2005 ORNL LDRD Self-Assessment (ORNL/PPA-2006/2) provides financial data about the FY 2005 projects and an internal evaluation of the program's management process. ORNL is a DOE multiprogram science, technology, and energy laboratory with distinctive capabilities in materials science and engineering, neutron science and technology, energy production and end-use technologies, biological and environmental science, and scientific computing. With these capabilities ORNL conducts basic and applied research and development (R&D) to support DOE's overarching national security mission, which encompasses science, energy resources, environmental quality, and national nuclear security. As a national resource, …
Date: April 1, 2006
Creator: Sjoreen, Terrence P
System: The UNT Digital Library
Corrective Action Investigation Plan for Corrective Action Unit 370: T-4 Atmospheric Test Site, Nevada Test Site, Nevada with ROTC-1, Revision 0 (open access)

Corrective Action Investigation Plan for Corrective Action Unit 370: T-4 Atmospheric Test Site, Nevada Test Site, Nevada with ROTC-1, Revision 0

Corrective Action Unit (CAU) 370 is located in Area 4 of the Nevada Test Site, which is approximately 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit 370 is comprised of Corrective Action Site (CAS) 04-23-01, Atmospheric Test Site T-4. This site is being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and/or implement a corrective action. Additional information will be obtained by conducting a corrective action investigation (CAI) before evaluating corrective action alternatives and selecting the appropriate corrective action for this CAS. The results of the field investigation will support a defensible evaluation of viable corrective action alternatives that will be presented in the Corrective Action Decision Document. The investigation results may also be used to evaluate improvements in the Soils Project strategy to be implemented. The site will be investigated based on the data quality objectives (DQOs) developed on December 10, 2007, by representatives of the Nevada Division of Environmental Protection; U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office; Desert Research Institute; Stoller-Navarro Joint Venture; and National Security Technologies, LLC. The DQO process was used to identify and define the type, amount, and quality of …
Date: April 1, 2008
Creator: Matthews, Pat
System: The UNT Digital Library
Facility Configuration Study of the High Temperature Gas-Cooled Reactor Component Test Facility (open access)

Facility Configuration Study of the High Temperature Gas-Cooled Reactor Component Test Facility

A test facility, referred to as the High Temperature Gas-Cooled Reactor Component Test Facility or CTF, will be sited at Idaho National Laboratory for the purposes of supporting development of high temperature gas thermal-hydraulic technologies (helium, helium-Nitrogen, CO2, etc.) as applied in heat transport and heat transfer applications in High Temperature Gas-Cooled Reactors. Such applications include, but are not limited to: primary coolant; secondary coolant; intermediate, secondary, and tertiary heat transfer; and demonstration of processes requiring high temperatures such as hydrogen production. The facility will initially support completion of the Next Generation Nuclear Plant. It will secondarily be open for use by the full range of suppliers, end-users, facilitators, government laboratories, and others in the domestic and international community supporting the development and application of High Temperature Gas-Cooled Reactor technology. This pre-conceptual facility configuration study, which forms the basis for a cost estimate to support CTF scoping and planning, accomplishes the following objectives: • Identifies pre-conceptual design requirements • Develops test loop equipment schematics and layout • Identifies space allocations for each of the facility functions, as required • Develops a pre-conceptual site layout including transportation, parking and support structures, and railway systems • Identifies pre-conceptual utility and support system …
Date: April 1, 2008
Creator: Austad, S. L.; Guillen, L. E.; Ferguson, D. S.; Blakely, B. L.; Pace, D. M.; Lopez, D. et al.
System: The UNT Digital Library
Possible Depolarization Mechanism due to Low Beta Squeeze (open access)

Possible Depolarization Mechanism due to Low Beta Squeeze

Simulations reveal a potential depolarization mechanism during low beta squeeze. This depolarization appears to be driven by a spin tune modulation caused by spin precession through the strong low beta quads due to the vertical fields. The modulation of the spin tune introduces an additional snake resonance condition at {nu}{sub s0} {+-} n{nu}{sub x} - {nu}{sub z}l = integer which while the same numerology as the well known sextupole resonance, can operate in the absence of sextupole elements.
Date: April 1, 2008
Creator: Ranjbar,V.; Luccio, A. & Bai, M.
System: The UNT Digital Library
Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2005 Through September 30, 2006 (open access)

Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2005 Through September 30, 2006

The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2006. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.
Date: April 1, 2007
Creator: King, James F.
System: The UNT Digital Library
Xenon Gamma Detector Project Support (open access)

Xenon Gamma Detector Project Support

This project provided funding of $48,500 for part of one year to support the development of compressed xenon spectrometers at BNL. This report describes upgrades that were made to the existing detector system electronics during that period, as well as subsequent testing with check sources and Special Nuclear Materials. Previous testing of the equipment extended only up to the energy of 1.3 MeV, and did not include a spectrum of Pu-239. The new electronics allowed one-button activation of the high voltage ramp that was previously controlled by manual adjustments. Mechanical relays of the charging circuit were replaced by a tera-ohm resistor chain and an optical switch. The preamplifier and shaping amplifier were replaced by more modern custom designs. We found that the xenon purity had not been degraded since the chamber was filled 10 years earlier. The resulting spectra showed significantly better resolution than sodium iodide spectra, and could be analyzed quite effectively by methods using peak area templates.
Date: April 1, 2008
Creator: Vanier, P. E. & Forman, L.
System: The UNT Digital Library
Development of Automated Production Line Processes for Solar Brightfield Modules: Final Report, 1 June 2003-30 November 2007 (open access)

Development of Automated Production Line Processes for Solar Brightfield Modules: Final Report, 1 June 2003-30 November 2007

Summary of progress by Spire Corporation under NREL's PV Manufacturing R&D Project to develop new automated systems for fabricating very large photovoltaic modules.
Date: April 1, 2008
Creator: Nowlan, M.
System: The UNT Digital Library
Optical diffraction radiation from a beam off a circular target (open access)

Optical diffraction radiation from a beam off a circular target

The use of optical diffraction radiation (ODR) as a diagnostic tool has increased in recent years. The potential of this technique has been demonstrated in several experiments at KEK [1], APS [2], FLASH [3] and possibly other facilities. These experiments were performed in extraction beam lines of lepton machines. However this technique can also be applied to high energy hadron beams. In this report we consider the ODR produced by such beams with the target as a round hole and apply the results to the Tevatron. This radiation is produced when a beam passes in the vicinity of a conducting target. The electro-magnetic fields due to the beam induce currents on the target and as the beam propagates, the currents change in time producing radiation both in the direction of beam propagation and along the direction of specular reflection from the target. This latter radiation, also termed backward diffraction radiation (BDR), is more useful for diagnostics since it can be directed out at the same longitudinal location as the target. This radiation is different from optical transition radiation (OTR) in which the beam passes through a metal target. Transition radiation is not suitable for continuous monitoring of a beam in …
Date: April 1, 2008
Creator: Sen, Tanaji
System: The UNT Digital Library
Statistical validation of engineering and scientific models : bounds, calibration, and extrapolation. (open access)

Statistical validation of engineering and scientific models : bounds, calibration, and extrapolation.

Numerical models of complex phenomena often contain approximations due to our inability to fully model the underlying physics, the excessive computational resources required to fully resolve the physics, the need to calibrate constitutive models, or in some cases, our ability to only bound behavior. Here we illustrate the relationship between approximation, calibration, extrapolation, and model validation through a series of examples that use the linear transient convective/dispersion equation to represent the nonlinear behavior of Burgers equation. While the use of these models represents a simplification relative to the types of systems we normally address in engineering and science, the present examples do support the tutorial nature of this document without obscuring the basic issues presented with unnecessarily complex models.
Date: April 1, 2005
Creator: Dowding, Kevin J. & Hills, Richard Guy (New Mexico State University, Las Cruces, NM)
System: The UNT Digital Library